BBAH

In collaboration with Prof. Yang Qu (UNB), we identify and characterize three new cytochrome P450 (CYP) enzymes that facilitate regio- and stereospecific oxidation of four monoterpene alkaloid (MIA) skeletons: iboga, aspidosperma, pseudoaspidosperma, and quebrachamine. From […]

We unveil and characterize a new N-methyltransferase (NMT) enzyme from the plant T. elegans: perivine Nβ-methyltransferase (TePeNMT). Enzyme kinetic experiments and enzyme homology modeling studies reveal the significant differences in enzyme active sites between TePeNMT […]

For many years we have sought computational support for the bent bond/antiperiplanar hypothesis (BBAH). The concept of geminals1 (two-electron orbitals) in quantum chemistry addresses many of the inherent issues stemming from the one-electron formalism that […]

A new mechanism for the thermal and photochemical Diels-Alder cycloaddition based on the bent bond/antiperiplanar hypothesis orbital model  The thermal and photochemical stereochemical reactivity of norbornene derivatives (Diels-Alder, retro- Diels-Alder, Cope rearrangement) can be rationalized […]

Stereochemistry of Eʹ and Eʹʹ decarboxylative-dehydration reactions and the bent bond / antiperiplanar hypothesis orbital model The known concerted decarboxylative-dehydration reaction of unsaturated hydroxy-carboxylic acids is analyzed through the Bent Bond/Antiperiplanar Hypothesis (BBAH), which considers […]

Revisiting the conformational analysis of unsaturated organic compounds using the bent bond / antiperiplanar hypothesis The bent bond/antiperiplanar hypothesis (BBAH) offers a straightforward qualitative model for interpreting the conformational analysis of simple unsaturated acyclic systems, […]

Bent bond / antiperiplanar hypothesis and antiaromatic, aromatic and nonaromatic molecules The stereochemical reactivities of monocyclic unsaturated compounds having 3–5 and 7–8 membered rings and of bicyclic pentalenes and heptalene can be rationalized through the […]

The conformation and reactivity of butadiene and the bent bond/antiperiplanar hypothesis orbital model The bent bond/antiperiplanar hypothesis (BBAH) is a useful orbital model explaining the conformational analysis and chemical reactivity of butadiene, the regioselective isomerization […]

The thermal rearrangements of naphthalene and azulene. An analysis through the bent bond and antiperiplanar hypothesis orbital model The thermal conversion of azulene, naphthalene, norcaradiene, and polycyclic analogues can be rationalized through the Bent Bond/Antiperiplanar […]

The bent bond / antiperiplanar hypothesis and the thermal rearrangement of cyclopropyl halides and tosylates The mechanism of solvolysis of cyclopropyl halides and tosylates yielding allylic products is deduced at the molecular level through the […]